There are a large number of known connectors for connecting external components to units used in medical technology. The access to the units used in medical technology is generally gained by means of plugs which are plugged into mating sockets on the units used in medical technology. This being the case, the units used in medical technology, which will be referred to in what follows as items of medical apparatus, have a suitable socket unit while the external components have a plug unit.
What are used to treat patients suffering from kidney diseases are items of blood treatment apparatus which include in particular the known items of extra-corporeal blood treatment apparatus or items of apparatus for peritoneal dialysis. For the patient's blood to be cleansed, it is necessary for medical treatment fluids to be supplied. These include for example dialysis fluid or substitution fluid. In what is known as automatic peritoneal dialysis (APD) or acute dialysis, the medical treatment fluids are processed automatically in the blood treatment apparatus. The treatment fluids are supplied in fluid reservoirs which are connected to the treatment apparatus. The fresh dialysis fluid is pumped from the fluid reservoir into the blood treatment apparatus and used fluid is pumped out of the treatment apparatus and into the fluid reservoir. The fluid reservoir may already contain a concentrate which needs to be diluted with water. When this is the case, the fluid reservoir merely needs to be filled with water. Because of this, water too is understood to be a medical fluid in this connection. It is also possible for there to be a plurality of fluid reservoirs connected to a blood treatment apparatus when a treatment fluid ready for use is produced in the treatment apparatus by mixing a plurality of fluids. The liquid reservoir is once again connected to the blood treatment apparatus by a plug unit which is inserted in a socket unit on the blood treatment apparatus.
For filling the device for supplying dialysis fluid, there are known items of apparatus to which the devices for supplying dialysis fluid can be connected. For this purpose, the items of filling apparatus once again have a socket unit which can be connected to the plug unit of the device for supplying dialysis fluid.
A device for supplying a treatment fluid is described in, for example, European Application No. EP 0 575 970 A2. This device for supplying dialysis fluid comprises a bag for receiving the fluid, to which is connected a flexible line which is connected to a plug at its free end. The dialysis apparatus has a socket into which the plug is plugged. With the plug and socket, it is possible to make two flow-permitting connections to enable fresh dialysis fluid to be conveyed out of the bag and into the dialysis apparatus and used dialysis fluid to be conveyed back into the bag.
When the device for supplying medical fluids is being filled, it must be ensured that the possibility of the device for supplying medical fluids being re-used is ruled out.
European Application No. EP 0 476 089 B1 describes a device for irrigating tissues which has a module to receive a cassette intended for once-only use. The module has an undercut recess into which a projection in hook form on the cassette fits when the cassette is inserted in the module. When the cassette is withdrawn from the module, the projection in hook form breaks off. Described in European Application No. EP 0 947 206 is a plug unit of a device for supplying dialysis fluid which has a bar code.